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SKYWatch: Jupiter

On November 4th, we tracked three of Jupiter's moons for
several hours. Io can be seen disappearing behind Jupiter,
then re-appearing. Use Guy Ottewell's Astronomical Calendar 1999 to figure out which
moon is which. Which way are the moons traveling in their orbit? (The telescope
was set up in alt/az mode; that is why the plane of Jupiter and its moons does not
remain horizontal on the image. If the telescope were set up in equatorial mode, the image
would not seem to rotate.)

When you open the
images of Jupiter, you have to adjust the display to see the moons. These images
show the moons because log scaling is checked. Without log scaling you can see the
bands in the atmosphere of Jupiter. Use the axes tool to find the center of Jupiter,
then use slice to measure from a moon to Jupiter's center in each of the images.
These tools can help you figure out how the moons are moving with respect to
Jupiter.